A variety of processes and purification techniques have heretofore been proposed or used for extracting all or selected ones of a variety of normally-occurring contaminating metals and/or metal compounds in technical grade molybdenum oxide concentrates. The removal of such contaminating cations is necessary to provide a molybdenum oxide or ammonium molybdate product of satisfactory purity to enable its use in the synthesis of various molybdenum compounds, in the production of molybdenum catalysts and such other uses requiring a high purity molybdenum metal. Perhaps the principal objection to prior art purification processes has been the high cost and/or low yields associated with their operation, rendering them commercially unacceptable from an economic standpoint. In many instances, the large volume of waste streams generated in the course of such purification processes has occasioned a considerable investment in waste treatment equipment and in chemical reagents, still further detracting from the overall economics of such purification processes.
The process of the present invention overcomes many of the problems and disadvantages associated with prior art type purification processes in enabling the purification of technical grade molybdenum oxide concentrates to a substantially high purity molybdenum product at commercially attractive costs and without the generation of voluminous waste streams, thereby eliminating costly pretreatments prior to discharge to waste.